Refillable cartridge-fuse



L. COOLEY.

REHLLABLE CARTRIDGE FUSE.

APPLICATION FILED JAN. 8. 1919.

UNITED STATES PATENT OFFICE.

REFILLABLE CARTRIDGE-FUSE.

Application filed January 8, 1919.

To all whom it may concern.

Be it known that I, FRANK L. CooLEY, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Refillable Cartridge-Fuses; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to characters of reference marked thereon, which form a part of this specification.

The present invention has reference, generally, to improvements in cartridge fuses; and the invention relates, more particularly, go a novel construction of refillable cartridge use.

The invention has for its principal object to provide a novel and simple construction of refillable cartridge fuses involving improved structural features to accomplish the following objects, to wit: to provide improved means for securing the removable end ferrules, both to the ends of the casing in sealing relation to the chamber thereof, and in proper electrical contact with the fuse arranged within said casing; to provide an efficient support and disposition of the fuse link within said casing so as to properly center the blowing portion thereof; and to provide for other objects, not at this time more particularly enumerated, but which will be clearly understood from the following detailed description of the present in vention.

With the various objects of the present invention in view, the same consists, pri marily, in the novel construction of refillable cartridge fuses hereinafter set forth, and the invention consists, furthermore, in the novel arrangements and combinations of the various devices and parts, as well as in the details of the construction of the same, all of which will be hereinafter more fully described, and then finally embodied in the claims appended to this specification.

The invention is clearly illustrated in the accompanying drawings, in which Figure 1 is a side elevation of the novel construction of a refillable catrtridge fuse made according to and embodying the principles of my present invention; Fig. 2 is an end elevation of the same; Fig. 3 is a longitudinal vertical section through the same,

Specification of Letters Patent.

Patented Dec. 14, 1920.

Serial No. 270,113.

taken on line 3-3 in said Fig. 1, said view being drawn on an enlarged scale; Fig. 4 is another longitudinal section through the same, taken on line 4 -4 in said Fig. 3; Fig. 5 is a detail side elevation of one end of the cartridge casing showing the ferrule thereon broken away to show the mortised seat provided for the cross nut of theferrule fastening devices; and Fig. 6 is an end elevation of the cartridge fuse, with an end ferrule removed therefrom.

Fig. 7 is a detail longitudinal vertical sectlon, similar to that shown in Fig. 3, but illustrating the arrangement of knife-blade contact elements in connection with the ferrules of the cartridge fuse; Fig. 8 is another longitudinal section, taken on line 8-8 in said Fig. 7 and Fig. 9 is an end view of said construction, with the ferrule removed, and the position of the knife-blade contact element indicated in broken outline.

Similar characters of reference are employed in all of the hereinabove described views, to indicate corresponding parts.

Referring now to the said drawings, the reference-character 1 indicates a tubular casing, made of some suitable insulating or nonconducting material, which provides an interior fuse chamber 2.

Frovided in the walls at each end of said caslng 1 are a pair of transversely opposite mortised seats 3, the sides 4 of which incline inwardly toward the outer end of the casing. Dovetailed into said respective mortised seats 3 are the ends of a transversely disposed cross nut or anchor bridge 5, which is shaped in cross-section to correspond to the shape of said mortised seats, and which may be thrust or withdrawn endwise from said seats, but is held, by engagement in said seats, against outward displacement or withdrawal from the open ends of the said casing 1. Said cross nut or anchor bridge 5 is provided with a centrally disposed internally threaded opening 6.

The reference-character 7 indicates a removable fuse link, provided with end terminals 8 having perforations or openings 9 therein. Said fuse link, when properly assembled, passes longitudinally and diagonally through the fuse chamber 2, with its end terminals 8 extending over the cross nuts or anchor bridges 5, one terminal passing over the upper side of one cross nut or anchor bridge, and the opposite terminal passing under the lower side of the opposite cross nut or anchor bridge, thus assuring the diagonal disposition of the main body of the fuse linl: within the fuse chamber, so that the intermediate blowing portion thereof (subsequently described) is assured being centered in position intermediate oi the inner sides the walls of said casing 1. The respective end terminals 8 are turned over the outer 'aces of the respective metallie cross nuts or anchor bridg s 5, with their perforations or openings 9 alined over the internally threaded openings 6 of said cross nuts or anchor bridges, Tonnected integrally with one of said e terminals 8 of said fuse link 7 is an indicator tongue 1( adapted to extend over the in inal edge of the adjacent end of said ca ng 1, so to be doubled back over the exterior sine of said casing 1 in sruh a manner that its free end 11 is visibly exposed against tie exterior side of said casing 1 beyond the free marginal edge of the skirt of a ferrule (subsequently described) which is arran ed over said end of said casing 1. lnscrioed on said free end 11 of said indicator tongue is an indicating marl: 12 denoting the amperage capacity of the fuse link 7. TM feature of the construction of my novel refillable cartridge fuse is of peculiar advantage, in that the fuse link itself b the indication of its electrical capacity, i. such manner as to be externally visible when the fuse link is properly assemblec. with cartridge In consequence of this novel arrangement the user of the cartridge fuse or the inspector charged with the duty sceing that proper capacity fuses are used, is always assured that only a fuse linl: of a proper capacity for the conditions required of the cartridge fuse is employed, and 1nistakes in the replacement of use linlcs are rendered less likely of occurrc ce.

The reference-character 13 indicates the metallic external contact ferrules, the 2:

nular shirts 1% of which are telescopicall engaged over the ends of the casing 1, errules 13 are adapted to close the c the casing 1, and at the time electrically engage the end terminals 8 of the fuse link '7. l

Said ferrules 13 are constru ted in a novel manner for the purpose of so eng ing the open ends of the casing 1 as to securely seal the latter against the escape of flame therefrom when the fuse linl: blows, and at th same time the novel construction is such that a secure clamping of the end of the ferrules against the one terminals 8 of the fuse link, as the said terminals are backed by the cross nuts pr anchor bridges 5, is assured, whereby an efficient and con tain electrical contact of the ferrules with the fuse link is attained. To this end each ferrule 13 is provided in its end wall with an inwardly depressed and tapered con centric boss 15, the periphery 16 of which is carried into engagement with the marginal cage 1? of the opening of the casing ends in a sealing relation thereto in much the same way as a cork or stopper is engaged in the neck of a bottle. The transverse wall 18 of said boss 15 is provided with a centrally disposed perforation 1.), which, when the ferrule is in place, alines itself with the internally threaded opening 6 of said cross nut or anchor bridge and. the opening 9 of the end terminal 8 of the fuse link reg tered with the said threaded opening 6. A fastening screw 20 is inserted tnrough said pcrfor-ation 19, so as to pass through said open ing 9 of the fuse link terminal 8, and thus into threaded relation to the opening (3 of the cross nut or anchor bridges. The hcaul 21 of said screw 20 engages the outer surface of said transverse wall 18 of the be as 15. l v hen the screw 20 is screwed home it draws down the ferrule against the end of said casing 1 so as to first wed e the b 15 securely into the open end or the casing 1 in sealing relation thereto, and then by inwardly depressii'ig said transverse wall 18 forces the same firmly into certain electrical contact with the adjacent end terminal 8 of the fuse link, securely clamping the same between said transverse wall 18 and the outer face of said cross nut or bridge anchor over which it is enga ed. T he ferrule 13 engaged over the end or the casing 1 at which the indicator tongue of the fuse link is located, freely slides over said indirator tongue 10. The said indicator tongue 10, however, is of sufiicient length that its free end 11 projects beyond the free edge of the skirt of the ferrule, when the latter is secured in final assembled relation, so that said free end 11 is visibly exposed against the exterior side of the casing in a anner clearly disclosing the fuse capacity indication mark 12 inscribed thereon. The fastening screw being free to turn in the opening 19 of the transverse wall 18 of the ferrule boss 15, there is no turning or t visting movement imparted to the ferrule when being fastened in place thereby, and consequently no twisting or straining movement is imparted to the fuse link end terminals 8 tending to distort the same, or by fracture or breakage at such point tending to alter the fuse capacity.

The fuse link 7 is provided intermediate of its end terminals 8 with two or more longitudinally spaced perforations 22 of perly predetermined diameter relative to L118 width of the fuse linl; body. These perforations thus disposed determine the size of blow out portions 23 of the fuse accord ing to the amperage capacity oesireu of the fuse link, and the same time assure, as far as practically possible, that the fuse will blow at such points well withdrawn and centered within the interior of the fuse chamber 2 of the casing 1, thus avoiding likelihood of fusing the end terminals 8 to the ferrules or fastening means thereof, whereby disassembling of the said parts is prevented.

In the event an assembled fuse link blows when the cartridge is in use, the cartridge may be removed from the electric circuit it serves, and the ferrules taken off so that the blown fuse link may be removed, and a new replacement thereof made, whereupon the ferrules are again assembled in the above described relations to the renewed cartridge. It will also be clear that the novel construction of cartridge fuse above described comprises comparatively few parts of simple, strong and durable construction and arrangement, very easily manipulated for purposes of renewing the same after it is blown. The same being so arranged that the in terior fuse chamber 2 is practically sealed against the venting of flame therefrom upon the blowing of the fuse, so that not only does the cartridge fuse provide a high order of electrical efficiency when in use, but also provides a maximum of safety from all other standpoints.

I am aware that some changes may be made in the arrangements and combinations of the various devices and parts, as well as in the details of the construction of the same, without departing from the scope of my present invention as set forth in the fore going specification, and as defined in the appended claims. Hence, I do not limit my invention to the exact arrangements and combinations of the several devices and parts as described in the foregoing specification, nor do I confine myself to the exact details of the construction of the said parts so illustrated in the accompanying drawings.

I claim 1. A refillable cartridge fuse comprising a tubular casing having transversely opposite mortised seats in the ends of its walls, transverse cross members fixed within the open ends of said casing by dovetailing their ends into said mortised seats, a fuse link having end terminals engaged over said cross members, removable contact ferrules slidable over the ends of said casing, said contact ferrules having means engaging the open' ends of said casing to seal and close the same, and fastening means adapted to secure said ferrules respectively to said cross members and in electrical engagement with the end terminals of said fuse link.

2. A refillable cartridge fuse comprising a tubular casing having transversely opposite mortised seats in the ends of its walls, transverse cross members fixed within the open ends of said casing by dovetailing their ends into said mortised seats, a fuse link having perforate end terminals engaged over said cross members, removable contact ferrules slidable over the ends of said casing, the end walls of said ferrules having inwardly depressed bosses the peripheries of which are adapted to be pressed into sealing relation to the open ends of said casing, the transverse walls of said bosses having openings therein, and loose fastening screws adapted to be passed through said openings and thence through said fuse link terminals to screw into said cross members whereby said bosses are drawn to said sealing relation to the ends of said casing, and said transverse walls of said bosses depressed into electrical contact and mechanically clamping relation to said fuse link terminals.

3. A refillable cartridge fuse comprising a tubular casing having transversely opposite indented notches in the ends of its walls, the sides of said notches being restricted toward their open ends, cross mem bers of outwardly tapered cross-sectional shape, said cross members being movable endwise into said notches so that their ends dovetail into the latter to be thereby held against outward withdrawal from the ends of said casing, a fuse-link extending through said casing having its ends engaged respectively over said cross-members, removable contact ferrules slidable over the ends of said casing to retain said cross-members against endwise removal therefrom, means connected with said ferrules for sealing the ends of said casing, and detachable fastening screws adapted to screw into said cross members for securing said ferrules in sealing relation to said casing and in electrical contact with the ends of said fuse-link as engaged over said cross-members.

a. A refillable cartridge fuse comprising a tubular casing having transversely opposite indented notches in the ends of its walls, the sides of said notches being restricted toward their open ends, cross-members of outwardly tapered crosssectional shape, said cross-members being movable endwise into said notches so that their ends dovetail into the latter to be thereby held against outward withdrawal from the ends of said casing, a fuse-link having end terminals respectively engaged over opposite sides of said cross-members so that the body thereof passes diagonally through the interior of said. casing, removable contact ferrules slidable over the ends of said casing, the same serving to retain said cross-members against endwise removal from said notches, the end walls of said ferrules having depressed bosses the peripheries of which are adapted to be pressed into sealing relation to the open ends of said casin and detachable fastening screws adapted to In testimony that I claim the invention set forth above I have hereunto set my hand this 20th day of December, 1918.

FRANK L. COOLEY.

VJitnesses GEORGE D. RICHARDS, ADoLPH HANSON. 

